A long, long time ago, when I was working as a bag boy at a grocery store, I carried some groceries out to a ladies car. On the top of the cab, the sheet metal was raised about a quarter of an inch in a perfect circle. I asked her what happened and she said that she had a refill can of freon for the car in the back seat, and forgot about it and left it in the car with the windows up. She was in the house when she heard the explosion! Can you imagine what it would have been like to be in the car when it cooked off!
Same thing happened at the NAPA store where I worked decades ago; outside route driver left a case of it in the seat of the delivery truck over the weekend. The whole case of cans did that.